Engine output equalizing apparatus



Dec. 6, 1949 J. A. CAMPBELL ENGINE OUTPUT EQUALIZING APPARATUS 2Sheets-Sheet 1 Filed March 16, 1946 mm Ow NB ww wm in on Q. Wm mmwQwEmIP LNEN m2 Q mw 8 S 32w 8 mm m IN V EN TOR. James A. Campbell Dec.6, 1949 J. A. CAMPBELL 2,490,113

ENGINE OUTPUT EQUALIZING APPARATUS Filed March 16, 1946 2 Sheets-Sheet 2(N NCO Q OwT 01g 8 2239 Q 995 03 O l Qfiw-QN \O QQ 21 QEQQEQ 5% 9.-

T? to A 00 N J3 M m :2 E9. 323 0 E3 010) INVENTOR. Jam es A. Campbell FBY H '4' ATYURMFY Patented Dec. 6 1949 ENGINE OUTPUT EQUALIZINGAPPARATUS James A. Campbell, Berkeley, Calif, assignor to TheWestinghouse Air Brake Company, Wilmerding, Pa., a corporation ofPennsylvania Application March 16, 194.6, Serial No. 654,931

10 Claims.

This invention relates to control apparatus and more particularly tomeans for equalizing the power output of a plurality of prime moverssuch as internal combustion engines of the Diesel type.

One object of the invention is the provision of means for automaticallyequalizing the power output of a plurality of engines.

Another object of the invention is the provision of apparatus embodyingoperators control means for simultaneously adjusting the power output ofa plurality of engines, and means automatically operative in accordancewith a selected degree of power output of one of said engines to adjustthe power output of the other engine or engines to substantially thesame degree, in case the power output of said other engine or engines ismaterially different from that of said one engine.

In Diesel engines the position of the so-called fuel rack or shaft,which determines the amount of fuel supplied to the engine, isconsidered a most reliable and practicable index of engine output, andanother object of the invention is therefore the provision of meanswhich is automatically operative in accordance with the position of thefuel shaft on one engine to cause the fuel shaft on another engine orengines to assume substantially the same position.

Other objects and advantages will be apparent from the following moredetailed description of the invention.

In the accompanying drawings; Fig. 1 is a diagrammatic, elevational viewof a system for controlling the speed or power output of a plurality ofengines and embodying the invention; Fig. 2 is a diagrammatic view of aportion of a fuel control system for each of said engines; Fig. 3 is asectional view of a fuel or speed control motor for each of said enginesand shown in elevation in Fig. 1; Fig. 4 is a sectional view of apressure regulating valve device associated with each of said enginesand shown in elevation in Fig. 1; and Fig. 5 is a sectional view of anequalizing valve device shown in elevation in Fig. 1.

Description As shown in Fig. 1 of the drawings, the dot-dash lineenclosures designated A and B indicate two of a plurality of engines,the enclosure designated A constituting what may be called a masterengine, while the enclosure designated B constitutes, one of any desirednumber of engines to be controlled from engine A. Engine B may bereferred to as a slave engine.

Each of these engines may for the purpose of illustration be of theDiesel type comprising (Fig,

' 2) a conventional cam shaft l for operating through a cam 2 and a pushrod 3 an injector pump 4 for each engine cylinder, for supplying fuel tosaid cylinder through an injector pipe 5. The amount of fuel supplied tothe engine cylinder by pump 4 is adapted to be regulated by a pumpadjusting rack 6 operatively connected to a lever 1 on a fuel controlshaft 8. The fuel shaft 8 may have an engine idling position in which itis shown in the drawing for adjusting pump 4 to provide fuel to theengine cylinder in an amount sufficient to cause operation of the engineat an idling speed and may be turned in a clockwise direction, as viewedin Fig. 2, to adjust said pump to increase the fuel supply in proportionto the degree of such turning. A maximum amount of fuel will be providedto the engine in a position of the fuel shaft 8 such as indicated by adot-dash line 9. It will be understood that the engine may have anydesired number of cylinders and that a fuel pump 4, rod 3 and cam 2 willbe provided for each cylinder, and that the fuel shaft 8 Will beconnected to all fuel pumps, in accordance with conventional practice.

Adjustment of the fuel control shaft 8 on each engine may be controlledby a speed governor l0 which may comprise a centrifuge ll connected bygears Ila to the cam shaft I. Two oppositely arranged centrifugallycontrolled bell cranks l2 are pivoted at their knees on pins [3 incentrifuge I I. One end of each of the bell cranks 12 engages a collarI4 secured to a vertically movable plunger or rod l5 which is providedwith another collar IE engaged by one end of a governor control spring[1. The opposite end of spring I! is engaged by a movable follower [8against which bears an adjusting cam l9 pivoted on a fixed pin 20 andconnected by an arm 2| to a governor adjusting rod 22.

It will be apparent that when the engine is in operation turning the camshaft I, that centrifugal force of the governor bell cranks l2 will beopposed by the pressure of the control spring I! and that the upper endof said cranks will move away from rod [5 to a position in which saidcentrifugal force will balance the pressure of said spring, and therebyposition said rod in accordance with the pressure of saidspring. If thecam is turned in a clockwise direction to increase the pressure ofspring I! on collar Hi, the bell cranks l2 will be moved toward rod 15to permit said rod to move down a proportional degree, while if the camis returned toward the position in which it is shown in the drawing, therod l5 will be elevated correspondingly. In other words, when the engineis operating the rod i5 will assume a position corresponding to theadjustment of cam l9.

An operating arm 23 for the fuel control shaft 8 is connected by a link24 to one end of a lever 25. The opposite end of lever 25 is fulcrumedon a fixed pin 25, while intermediate its ends said lever is connectedby a pin 2? to the governor rod [5, whereby the fuel control shaft 8;will be posi-. tioned in accordance with the position of said rod and ofcam [9.

In the drawing the parts of the governor ill in= eluding cam i9, and thefuel. control-1 shaft 8. are. shown in the position which it may beassumed will provide for operation of. the engine at an idling speed.With the engine operating. if the cam i9 is now turned in a clockwisedirection the governor rod l5 and fuel control shaft 3 will move out ofidling position to a new position, corre-. sponding to the change inposition of said cam, to caus a proportional r a n. th amount o fuelsupplied. to the engine and tl'lereby a corre-z word n inoroaso o e oututo h n in The turning of cam 59 in the opposite. direction will resultin a corresponding reduction in the. amount of fuel supplied to the.engine. It will thusbe seen that by suitable adjustment of earn i9 thesupply of fuel to the engine may 9 adjusted to obtain any selecteddegree of power output from the engine.

On the master engine A, the governor control rod is connected to agovernor control motor. 3E while on the slave engine Bsaid rod is. con:nected to a governor control motor 31..

With but one exception, which will be. later brought out, the governorcontrol motor 3il ,on the master engine A and the motor 3i on the slave.engine B are. identical in construction, each comprising (Fig. 3) acasing containing a power piston 32, and a rod 33 connected at one endto said piston while the opposite end is, connected :1:

exteriorly of the casing to the governor control rod 23. The piston rod33 ext'ends through a pressure chamber 3% at one side of piston Blandthrough a bore in a head 35 closingtheopen end of said chamber, saidhead being provided witha plurality of grooves encircling, saidrod andcon: taining sealing rings 36 having sealing. and.slicl-. in contactwith said rod to prevent. leakage offluid. under pressure. from. saidchamber. The pressure chamber 34 is connected to a control passage 3'!through which fluid under'pressure is adapted to be supplied to andreleased froni said. chamber, in a manner and by means tobe laterdescribed. At the opposite side ofthe power. piston 52 is a non-pressurechamber 38 whichis open to atmosphere through a passage 39 and whichcontains a regulating spring 4t acting on said piston in opposition topressure. of fluid in pressure of fluid in pressure chamber 34.

Each of the governor. motors. further com; prises a plurality of spacedapart flexible dia; phragms 41, 42, 43, 44 and 45 arranged, in. the.-order named in coaxial relation with each; other and with the regulatingspring 49 and the power. piston 32, the diaphragm 4| being disposedmostremote from said piston. The several diaphragms are clamped around theiredges in the casing and are all connected together centrally for move-,.ment in unison by structure comprising followers. spacers, and securingmeans indicated generally in the drawing by reference numeral 45.. Thisstructure 46 includes a coaxially arranged sleeve; like member 47projecting from the diaphragm 45 through a bore in a wall 48 intothenon-pres: sure chamber 38 wherein it supports seat means 49 carryingthe end of regulating spring opposite that acting on the power piston32.

The sleeve-like member 4'? is hollow and provided with spaced apartslots 55 extending longitudinally thereof. Disposed within the member4'l is an element 5i constituting a fixed part of a valve structurewhich will be presently described, said element having radial fingers 52extending through the slots 5% and contacting a shoulder 53 on thepartition wall 43. The slots 5!] provides for longitudinal movement ofmember 43 relative to the element 55 and wall 48. Only one of the slots53 and fingers 52 are shown in the drawing.

Between the diaphragm and wall 48 is a non-pressure chamber 54 which isopen through a passage 55 to thenon-pressure chamber 38 and thence toatmosphere through passage 39.

The diaphragms 4i and 42 are of the same areas and cooperate to form anintermediate chamb 4 .i isa control pressure chamber 57' which is opentoa pipe 53. The pipe 53 at each engineisconnected to a control pipe 59extending to all the engines from an operators control device 60 whichis provided for regulating pressure of fluid in chamber 57 in all of thegovernor control motors 39 and Si simultaneously. A precompressed biasspring 6i, contained in chamber 5? in, each of the motors Stand 8|. hasone end bearing. against the diaphragm connecting structure 46. Theopposite end of the bias spring ii is supported on one or more pressureadjusting shims 62, while in the motor 39 associated. with the. masterengine A there is, provided an additional shim 63 under spring 65 forreasons. which will be later brought out. This additional shirn- 63constitutes the only structural difference between the governor controlmotor 39 employed on the master engine A and the governor control. motor3.! employed on the slave engine B.

The diaphragms 43, id and. 45 are. all of the same area but of largerarea than diaphragms 4i. and 42. Between thediaphragms 42 and 43 is achamber 54 which in the. governor control motor 3 on the master engineAisopen to at-. mosphere through a. passage 65a, while. on the slaveengine B said chamber, isopen throughsaid passage to a pipe 65 throughwhich fluid under pressure is adapted to be varied. in saidchamber,

amanne-r-which. will be later brought out.

The diaphragms 4,3 and 44 cooperate. to; forma chamber 66 whichisadapted to be constantly. supplied through a pipe 61 with fluid under.pres sure from any suitable source. Between the diaphragms 44 and 45 isa chamber 58 towhich passage 31 from the power piston pressure chamber34 is open.

The element 5;! supported on the casing; wall 4-8rsupports one end'of asleeve or valve seatmernber 69' which is slidably mounted in a suitablebore provided axially inthe diaphragm connect-v ing structure 46. Theseat member 69 extends into a chamber 7 instructure 46 which chamber isin constant communication through a port H with chamber 68. A sealingring 'i2 carriedby structure 46 engages the peripheral; surface ofmember 69 to prevent leakage of fluid under pres sure from chamber 70 tochamber 54.

The valve seat member 69 has a valve seat arranged for engagement by arelease valve T3 which is provided for controlling. CQmmunicationbetween a passage 14. open to chamber. 10 and a passage 15 opening tothe non-pressure chamber 38 by way' of slots 50in the element 41 andcham- At the opposite side ofdiaphragm ber 54. The release valve I3 isprovided on one end of a stem I6 slidably mounted in a bore in the valveseat member 69 and extending into chamber I8 wherein said stem isprovided with an enlarged head 11. Interposed between one side of headI1 and the adjacent end of member 69 is a coil bias spring I8 which iseffective to urge the release valve I3 out of engagement with its seat.

The opposite side of head I! on the release valve stem I6 engages aprojection I9 of a co-' axially arranged fluid pressure supply valve 88which is contained in a chamber 8| provided in the structure 46. A seatis provided on structure 46 for the supply valve 88, and the projection19 extends through an opening encircled by said seat, said opening beingof greater area than said projection. Chamber 8| is in permanentcommunication through a port 82 in structure 46 with chamber 66 and thuswith the fluid pressure supply pipe 61. The supply valve 88 is providedfor controlling flow of fluid under pressure from the supply pipe 6! tochamber I8 and thence to chamber 68 and through passage 31 to chamber 34at the outer face of the power piston 32.

The supply valve 88 is formed on one end of a fluted stem 83 which isslidably mounted in and extends through a bore in structure 46 into achamber 84 which is open through one or more ports 85 to chamber 56between diaphragms 4| and 42. A coil bias spring 86 contained in chamber84 acts on the valve stem 83 for urging the supply valve 88 in thedirection of its seat. Chamber 56 is adapted to be constantly suppliedwith fluid under pressure from the supply pipe 65 by 3.1

way of the fluted valve stem 83.

In the governor control motor 3| on the slave engine B chamber 64between diaphragms 42 and 43 is adapted to be charged through pipe 65with fluid, by means to be later described, either at or above or belowsome chosen degree such as 25 pounds, and since diaphragm 43 is ofgreater area than diaphragm 4|, this pressure will create a force actingin the direction of the left hand on structure 46. In the governorcontrol motor 38 on the master engine A, in which diaphragm chamber 64between the diaphragms 42 and 43 is opened to atmosphere, the additionalshim 63 under spring 6| provides the same force on structure 46 actingin the direction of the left hand as obtained by the chosen pressure (25pounds) provided in chamber 64 in the governor control motor 3| on theslave engine B. This additional shim 63 in the governor control motor 38on the master engine A automatically conditions said engine to act asthe master for controlling the output of the slave engine.

Assocated with each of the engines is a pressure regulating valve device98 arranged to be controlled by the respective fuel shaft 8 forproviding in a pipe 9| fluid at a pressure proportional to the positionof said shaft and hence proportional to the amount of fuel supplied tothe engme.

Each of the pressure regulating valve devices 98 comprises a casingcontaining two spaced apart and coaxially arranged flexible diaphragms92 and 93 of the same areas and clamped around their edges in thecasing. Between the two diaphragms 92 and 93 is a chamber 94 open to afluid pressure supply pipe 95 and thus adapted to be constantly suppliedwith fluid under pressure. The chamber 94 is formed in two partsseparated by a wall 96 but in constant communication with each otherthrough a passage supply chamber 9 3.

91 in said wall. At the opposite side of diaphragm 93 is a non-pressurechamber 98 which is open to atmosphere through a breather port 99. Atthe oppsite side of diaphragm 92 is a chamber I88 open through astabilizing choke I8I to a chamber I82 to which pipe 9| is connected.

Disposed in chamber 94 is a stem I83 having one end connected to thecenter of diaphragm 93 by follower plates I84 and a clamping nut I85.The opposite end of stem I83 is in the form of an enlargement I86extending centrally through the diaphragm 92 and cooperating with a nutI8'I in chamber I88 to secure said stem to diaphragm 92 through themedium of follower plates I88. A coil regulating spring I89 encirclingstem I83 within chamber 94 has one end engaging vthe casing wall 96,while the opposite end acts against the enlargement I86 through themedium of a spring follower H8. With spring I89 fully expanded, thediaphragm 92 and 93 and the stem I83 will assume a position such asshown in Fig. 4 of the drawing.

In the stem enlargement I86 is a chamber III open through a passage II2to the fluid pressure A fluid pressure supply valve H3 contained inchamber III has a fluted. stem H6 extending through an axial bore in nutIiII into a chamber II formed within an extension II6 of said nut. Theextension H6 is mounted to slide in a sleeve II? which extends from theexterior of the casing through cham ber I82 and a wall separating saidchamber from chamber I88. Chamber II5 Within the nut extension II6 isopen through one or more ports H8 in sleeve II! to chamber I82.

The end of the supply Valve stem II4 engages in chamber H5 a fluidpressure release valve II9 having a fluted stem I28 mounted to slide ina bore provided axially of a plunger I2I which is slidably mounted insleeve I I1 above the nut extension IIB, said plunger being providedaround the end of said bore open to chamber II5 with a seat forengagement by said release valve. The release valve stem I28 extendsinto a chamber I22 in plunger IZI, said chamber being in constantcommunication with atmosphere through registering ports I23 in saidplunger and the sleeve III. Chamber I22 contains a bias spring I24acting on the release valve II9 for urging it away from its seat, whilein chamber III containing the supply valve I I3 is a spring I for urgingsaid valve into contact with its seat, the spring I25 exerting a greaterforce on the supply valve H3 than is exerted by spring I29 on therelease valve III-I. The plunger I2I has an annular groove carrying asealing ring I26 having sliding contact with the interior surface ofsleeve I I? for preventing leakage of fluid under pressure from chamberI I5 past said plunger to atmosphere.

Outside of the casing and beyond the adjacent end of sleeve II? is aspring seat I 2'8 secured to plunger I2I, and a coil spring I28encircling said sleeve and supported on the casing bears against saidseat for urging said plunger in a direction away from the release valveII9. Above the spring seat I21 an adjusting screw I29 is connected toplunger I2I by screw-threaded engagement and is locked in an adjustedposition by a lock nut I38 mounted on said screw and engaging theadjacent end of said plunger. The adjusting screw I29 is engaged by oneend of a bell crank I3I which at its knee is pivoted on a pin I32carried in an arm I33a projecting from the casing. The opposite end ofthe bell crank I3I is operatively connected to one end of a link I33 theopposite end of which isconnected to one end of. an

arm I34 which is mountedon the respective en: gine fuel control shaft 8for movement therewith,

With the fuel control shaft 8 on each engine in its engine idlingposition, screw lie in the respective regulating valve device 9i} may beturned out of plunger I2I for urging said plunger. in adownwardlydirection against springs iii} and iEdxtoa position in which it is incontact with the release valve I I9, with the supply valve i I3 seatedby.

spring. I25 and with the spring we fully expanded,

The screw I29 may then be locked to the plunger I2I by the lock nutI3il.

If the fuel control shaft 8 on either engineis rocked out of its idlingposition in which it is shown in the drawing this movement will actuatearm I35 and link its to rock the bell crank I31, ina correspondingdirection to move plunger I2I- in the direction of the supply valve Ii3, and with the release valve IE9 seated against the end of saidplunger said supply valve will be opened to permit flow of fluid underpressure from chamber 84. and the supply pipe as to chamber HE andthence through port i it to chamber i232 and pipe 9 I. At the same timeas fluid thus flows to pipe 9 i.

it will equalize through the stabilizing choke It! into chamber ledandtherein act on diaphragm 92. in opposition to pressure of theregulating spring IilQ. When the pressure of fluid in chamber Iild thenbecomes sufficient to overcome the force of regulating spring 982; thediaphragm 92 will deflect against said spring.

Now assuming that movement of the fuel con.-

trol shaft 8 has ceased in some position out of its idling position,movement of plunger I2I and thereby of the release valve i It and supplyvalve H3 will also have stopped, as a result of which, deflection ofdiaphragm by increasingpressure of fluid in chamber will be relative tosaid supply valve until said supply valve becomes seated. Seating of thesupply valve l 53 will then prevent further flow of fluid under pressureto chambers Hi2 and Idfi and pipe Q i, whereupon deflection of diaphragm32 will cease since the pressure of regulating spring I99 will have beenincreased sufliciently to counterbalance the pressure of fluid inchamber Hit. The increase in pressure of fluid in pipe BI will thereforebe limited to a degree dependent upon the extent of movement of the fuelcontrol shaft 3 out ofits idling position.

If the fuel control shaft 8 is moved further out of its idling positionthe respective pressureregulating valve device as will again be operatedto increase the pressure of fluid in the respective pipe 9! to a degreecorresponding to the degree of such movement. A maximum pressure offluid will be obtained in pipe 9! when the fuel control shaft 8 is movedto its full fuel position, indicated by the dot-dash line 9.

On the other hand, if the fuel control shaft 8v is moved in thedirection of its idling position, assuming that it is out of saidosition, this movev ment will rock bell crank i3: to permit movement. ofplunger ME by spring I28 plus pressure of fluid in chamber l I acting onsaid plunger in. a direction away from the supply valve Hit. With thesupply valve H3 seated, the release valve spring 524 will hold therelease valve lid against. movement with plunger 5 2 I, so that thismovement'of plunger IE! will be away from said release valve. to therebyopen communication past said release valve. for releasing fluid underpressure from chamber I02 and pipe 9|, and also from chamber I00 abovediaphragm 92. As the pressurecf fluid 8; inchamber I; is thus. reducedspring; I09. will deflect the diaphragm 92; in the direction of plungerIZI and during such movement spring 425 will move the supply valve I I3and the release valve I -I 9 along with said diaphragm. Assuming thatthe fuel control shaft 8 is stopped in a position, out of idlingposition, movement of plunger IZI will cease in a correspondingposition, so that:

movement of the release valve [I9 with diaphragm 92 will then berelative to said plunger until it engages its seat for preventingfurther release-of fluid. under pressure from chamber I02, pipeill andchamber [.60. When the release valve IIS is thus closed preventingfurther release of fluid under pressurev from chamber Illll, diaphragm92 will stop moving since the pressure of fluid in said chamber willjust counterbalance the-pressure of regulating spring I09. Thus the piessureof, fluid in pipe ill will only be, reduced tor v degree;corresponding to the position of the fuel control shaft 8 out of idlingposition. If the, fuel control shaft is moved further toward, but notcompletely to, its idling position the regulating valve devicefill willagain operate as just. described to effect a corresponding reduction inpressureof fluid in pipe 9I, while if said shaft is returned to its idleposition the parts of the regulating valve device will return to theposition.

shown in Fig. 4 in which the release valve H9 Willjust contact its-seatat the time-the pressure offluid in pipe 9i becomes reduced. tosubstantially atmospheric pressure and spring I09 becomes fullyexpanded.

It will noW be seen that the regulating valve device 99 on each enginewilloperate toprovide in the respective pipe 9I1 a. pressureproportional to the position of the respective fuel-control shaft 8,andhence proportional to the amount of fuel.

supplied to the engine, and it is desired to further point out; that theregulating valve devices Qt: on both the master and slave enginesareadjusted the same, so as to provide the same pressures in. therespective pipes 9! for the same positions of the respective fuelcontrol shafts 8.

The pipe 9i at the master engine A is connected to what maybe called anequalizing pipe I35 adapted to extend to all slave engines, such asengine B. Associated with the slave-engine B is what may be calledanequalizing valve device I38 connected by a pipe I31 'to thesynchronizing pipe, H5 and also connected-to pipe 9| from the areconstantly subject to fluid at supply pressure. At the opposite face ofdiaphragm I 39 is a control chamber I45 which is open to pipe I31leading tov the equalizing pipe I35. At the opposite-face of diaphragmI38 is a control chamber I45 which is connected to pipe ilileading tothe pressure regulating valve device Bil-on the respective or slaveengine.

Extending through the-chamber Mil-and" the chamber dividing wall I42 isa stem I46 one end of WhlChlS clamped to the center of diaphragm newfollower plates I41 and aunt I48; The

opposite end of stem I46 is connected to the center of diaphragm I38 byfollower plates I49 engaging opposite faces of said diaphragm and aclamping nut I50 disposed in chamber I45. The casing of the device alsohas a chamber II to which pipe 65 from the governor control motor 3| onthe respective engine is connected. Chamber I5I is separated fromchamber I45 by a wall I 52, and extending from the exterior of thecasing through chamber I5I and wall I52 and having one end open tochamber I45 is a bushing I53 arranged in coaxial relation with thediaphragms I38 and I39 and with the nut I50. The nut I50 has acylindrical extension I54 slidably mounted in an axial bore provided inthe adjacent end of bushing I53, and encircling and having sealing andsliding contact with said extension is a ring I55 carried in a groove insaid bushing. The interior of the extension I54 is open to a chamber I56formed within the bushing and said chamber is open through one or moreports I51 to the casing chamber I5l.

One end of chamber I56 within the bushing I53 is closed by a nut I58secured in said bushing. Secured in the nut I58 is an element I59 havinga bore arranged in coaxial relation to the flexible diaphragms I38 andI39, and in said bore is slidably mounted a pin I60. The pin I60 isprovided in chamber I56 with an enlarged head I6I while on the oppositeend of said pin is a fluid pressure release valve I62 arranged tocooperate with a seat on the nut I58 for controlling communicationbetween a passage I63 extending through the element I59 to chamber I56,and a passage I64 which leads to atmosphere, Interposed between the nutI58 and the stem head I6I is a light Spring I65 for moving the releasevalve I62 out of contact with its seat.

A pin I66 projects from the release valve stem head I6I centrallythrough the cylindrical extension I54 and an opening I61 in nut I50 toengage a fluid pressure sup-ply valve I68 which is contained in achamber I69 formed in the diaphragm clamping nut I50. The nut I50 has aseat for the supply valve I68 around the opening I61, which opening isof greater diameter than pin I66. The supply valve I68 is provided onone end of a fluted stem I which is mounted to slide in a bore extendingthrough the nut I 50 to a chamber I1I formed below said nut in thediaphragm connecting stem I46. Chamber I1I is connected through one ormore ports I12 to the fluid pressure supply chamber I40 between the twodiaphragms I38 and I39, and in chamber I1I the supply valve stem I1I isprovided with a head I13 against which acts one end of a coil spring I14the opposite end of which is supported by a wall in stem I46. A coilspring I contained in chamber I44 acts on the adjacent diaphragmfollower plate I41 for opposing movement of the diaphragms I36 and I39and of nut I50 in a direction against said spring.

In the equalizing valve device I36 it will now be noted that diaphragmI39 is subject in chamber I44 to pressure of fluid from the equalizingpipe I35 through pipe I31, that is, subject to pressure of fluidprovided by the pressure regulating valve device 90 on the master engineA, while diaphragm I38 is subject in chamber I45 to pressure of fluidprovided by the pressure regulating valve device 95 on the slave engineB. 'It will further be noted that pressure of spring I14 acting to seatthe supply valve I68 will oppose movement of the diaphragms I38 and I39and the connecting stem I46 by an increase in pressure of fluid indiaphragm chamber I44 over that effective in chamber I45, while springI15 will oppose movement of said diaphragms and stem in the oppositedirection by a preponderant pressure of fluid in chamber I45. Thesprings I14 and I15 are so proportioned as to require a definite orfixed differential, such as eight-tenths of a pound, between fluidpressures in chambers I44 and I 45, acting in either one direction or inthe opposite direction, to move the diaphragm and connecting stem I46,and this differential will remain substantially the same regardless ofthe pressure of fluid which may be effective in said chambers, incontrast to devices like the pressure regulating valve devices whereinthe force required through lever 3! to control the device will vary inproportion to variations in the opposing pressure of fluid effective inchambers I02 and H5 and acting on the plunger I2I plus the variablepressure of the bias spring I28.

The opposing forces of springs I14 and I 15 on the diaphragms I38 andI39 and the connecting stem I46 is also adapted to insure movement ofthese parts to a neutral or lap position in which both the supply valveI68 and release valve I62 are seated, as shown in the drawing, when thediiferential between the pressures of fluid in chambers I45 and I44 isless than the chosen differential above mentioned.

When a speed governor controlled engine is in operation, the speedgovernor is usually constantly operating within a limited range to matchthe fuel supply to slight variations in engine load or speed, and as aconsequence, the pressure regulating valve devices 90 on both the masterand slave engines A and B, respectively, will cause corresponding slightvariations in the pressure of fluid in the respective chambers I44 andI45 of the equalizing valve device I36, and another purpose of springsI14 and I15 is to prevent the parts of said device from moving out oftheir neutral position in response to such variations in fluid pressure.

In pipe 65 is a choke I16, and connected to said pipe between said chokeand the governor control motor 3I on slave engine B is a volume orreservoir I11,

Operation In operation, let it be initially assumed that the engines Aand B are stopped, that the operators control device 60 is opening thecontrol pipe 59 and diaphragm chambers 51 in the motors 30, 3| toatmosphere, and that the whole system is void of fluid under pressure.On each engine, the upper ends of the governor bell cranks I 2 will thenbe moved by the governor control spring I1 into substantial contact withplunger I5 and said plunger will be effective through lever 25, link 24and arm 23 to move the respec ive fuel control shaft 8 to its maximumfuel position, indicated by the dot-dash line 9 in Fig. 2. With the fuelcontrol shaft 8 at each engine thus positioned, the arm I 34 thereon andlink I33 will hold lever I3I of the respective fluid pressure regulatingdevice 90 to its maximum pressure position in which plunger I2I will beseated against the reease valve H9 and said valve will be unseating thesupply valve II3 from the nut I01.

Further, with the system void of fluid pressure the power piston 32 inthe governor control motors 30 and 3I will be in contact with a stop I18under the pressure of spring 40. In the governor motor 3! on slaveengine B the pressure of spring 40 on one end of the dia- 11 phragmconnecting structure 46 will thereby be reduced to a degree which willpermit control spring BI, as precompressed only by the shims '62, tohold said structure in the position for seating the release valve 13 andin which position the supply valve 80 will also be seated by spring 86.In the governor motor 39 on master engine A the pressure of theadditional shim 63 under the control spring 6| will .however increasethe force of said spring to a degree which will move the structure 4%against the regulating spring 40 and relative toithe seated releasevalve I3 to permit opening of the supply valve '80 by :said releasevalve. 7

Now let it :be assumed that pipes 95 of the .pressure regulating valvedevices 30 and pipes 51 of the governor motors 30 and 31 are opened tothe source of fluid under pressure. On the master engine A fluid underpressure thus supplied ;to pipe 95 will flow to chamber 94 in therespective pressure regulating valve devices 90 and "thence past theopen supply valve I3 to chambers 115 and H12 and from the latter'chamherthrough pipe 19:! to the equalizing pipe 135 and thence through pipe I31to diaphragm chamber I44 in the equalizing valve device I36. At the sametime as fluid is thus supplied to chamber I44 in the equalizing valvedevice l36 fluid will also flow from chamber E02 through the stabilizingchoke 1M to diaphragm chamber 100 in the pressure regulating valvedevice 90 on the master engine. When the pressure of fluid in chamber Ithen becomes increased suificient to overcome the opposing force ofregulating spring I09 the diaphragms B2 and 33 will be deflected inunison against said spring and relative to the supply valve II3 untilsaid supply valve becomes seated to prevent further flow of fluid underpressure to chambers 152 and I00 in the pressure regulating valve deviceand to chamber I44 in the equalizing valve device I36, so as to therebylimit the pressure of fluid obtained in said chambers to a maximumdegree corresponding to the maximum fuel .position of the fuel controlshaft 8 on engine vA.

On slave engine B the pressure regulating valve device 90 will alsooperate to supply fluid at a maximum degree of pressure, correspondingto a maximum fuel position of the respective fuel control shaft 8through pipe 9! to diaphragm chamber 145 in the equalizing valve deviceI36. Assuming that the supply of fluid to the two pressure regulatingvalve devices 90 is cut .in at the same time the pressures of fluid indiaphragm chambers I44 and I45 in the equalizing valve device I36 willbe increased substantially in unison and to the same maximum degree, asa result of which the parts of the equalizing valve device l36 willremain in the position in which they are shown in Fig. of the drawings.

When fluid under pressure is initially supplied to pipe 5] leading tothe governor control motor 3| on slave engine B it will merely flow intochamber 66 between the diaphragms 43 and 44, it being remembered thatthe supply valve 8% in said motor at this time is seated. Hence thepower piston 32 in motor 3| will remain in contact with the casing stopI18. However, in the fluid motor on master engine A, when fluid isinitially supplied through pipe 67 to chamber 66, fluid will flow pastthe open supply valve 8! into chamber I0 and thence through passage TIto chamber 68 between diaphragms '44 and '45 and "from the latterchamber through passage 3? to thepowerpiston chamber 34. Fluid underpressure will thus continue to flow to chamber 34 until it becomessuflicient to move piston 32 against spring '40 for increasing thepressure of said spring 'On the diaphragm connecting structure 46 to adegree suiiicient to move said structure against the control spring 6!relative to the supply valve and until said structure seats againstsa'id supply valve. When thesupply valve 80 in thegovernor motor as isthus closed the supply of fluid pressure to the power piston chamber .34will cease so that movement of the power piston 32 will also cease in aposition in which it is shown in Fig. 3 of the drawin and in which thefuel control shaft 8 will :be .in .its engine idling position. It willthus be seen that on the master engine A, the power piston 32 will bemoved away from stop I18 slightly upon initially cutting in the airsupply "to motor 30 and 3-1, while on slave engine .B the motor piston32 will still be in contact with stop H8; hence the pressure of spring Iin the governor on the master engine A will :be increased to 'a degreeslightly in excess of that enslave engine B.

Now let it be assumed that, with the oper- .ators control valve device69 still opening the control pipe '59 and thereby diaphragm chambers"5'! in 'the two governor control motors and 3! to atmosphere, the twoengines are started in any conventional manner.

As soon as the engines are started, rotation of centrifuge '31 by therespective cam shaft 2* will cause the upper ends of the governor bellcranks I2 to rock in a direction away from plungers it, due to theaction of centrifugal force the-eon, and to a position in which saidforce will counterbalance the adjusted pressure of the respectivecontrol spring I'I. On each engine this action of the governor arms I2will rock the fuel control shaft 8 out of its full fuel position, indicated by the dot-dash line 9, in the direction of its idling positionin which it is shown in Fig. 2, but since the pressure of the governorcontrol spring I? on slave engine B is less than that on the masterengine A, the governor control arms -52 on the slave engine B will moveout to a slightly greater degree and thereby operate the respective fuelcontrol shaft 8 to reduce the fuel supplied to the slave engine B to adegree slightly less than on master engine A, but still of a sufflcientdegree to ensure that the slave engine B will continue to operate.

When the two engines are started as just described operation of the fuelcontrol shafts 6 to reduce the amountof fuel supplied to the engineswill cause operation of the respective pressure regulating valve devicesto proportionately reduce the pressure of fluid in chambers M4 and I45in the equalizing valve device I35, it being noted that the pressure offluid in chamber M5 will reduce to a degree below that in chamber 544since the fuel control shaft 8 on slave engine B occupies a position forsupplying less fuel said slave engine than is being supplied to themaster engine A. As a result, a sufficient differential will be obtainedbetween the pressures of fluid in chambers I44 and I45 to deflect thediaphragms I38 and I39 against the supply valve seating spring IN tothereby move the nut use relative to the supply valve I68 so as to opensaid supply valve. Upon opening of the supply valve I68 fluid underpressure supplied through pipe MI to chamber I40 will flow past saidvalve to chamber I56 and thence through passage I51 to chamber HI andfrom the latter chamber through pipe 65 to diaphragm chamber 64 in thegovernor control motor 3| on slave engine B, the increase in pressure insaid chamber 64 being limited in rate by the restricting eifect of chokeH6 and the volume of reservoir I15.

When fluid under pressure is thus supplied to chamber 65 in the governorcontrol motor 3I on slave engine B as just mentioned, its effect on thedifferential areas of diaphragms 42 and 43 will create a force which,acting in conjunction with the respective control spring 6|, will movethe diaphragm connecting structure 46 in the direction of the left-handagainst the force of regulating spring 40 and thus out of seatingengagement with the supply valve 80 which is held against movement atthis time by the seated release valve 13. When the supply valve 80 inthe governor control motor 3| on the slave engine 13 is thus opened,fluid under pressure will flow from the supply pipe 61 past said valveto chamher it and thence to chamber 68 between the diaphragms 44 and 45and from the latter chamber through passage 3! to the power pistonchamber 34. When the pressure of fluid in chamber 34 is thus increasedsufliciently the power piston 32 will move against the regulating spring40 and increase the force of said spring against the diaphragm structure46, and when the force of said spring is consequently increased to asufficient degree said structure will move against the pressure of fluidin diaphragm chamber 54 and the pressure of the respective regulatingspring relative to and finally into contact with the supply Valve 8!!for preventing further flow of fluid under pressure to the power pistonchamber 34. This movement of the power piston 32 in the governor motor3! on slave engine B will in turn actuate cam I9 to increase thepressure of the governor control spring I! on said engine for therebycausing operation of the fuel control shaft 8 to increase the supply offuel to said engine to a degree determined by the increased pressure ofsaid spring and the centrifugal action of the governor control arm I2.

As the fuel control shaft 8 0n slave engine B is thus operated toincrease the supply of fuel to said engine the respective pressureregulating valve device 9!! will be operated to correspondingly increasethe pressure of fluid in diaphragm chamber I45 of the equalizing valvedevice E35 and when this pressure, acting in conjunction with springI14, becomes increased to substantially the same pressure as iseffective in chamber M4, the diaphragms I 38 and I39 will be movedagainst spring I and thus relative to the supply valve its until saidvalve becomes seated against the nut 556. When the supply valve N8 isthus seated further flow of fluid under pressure to chamber as in thegovernor control motor 3| on slave engine B will be prevented to therebylimit operation of said motor and of the respective fuel control shaft 3for increasing the supply of fuel to said engine relative to thatprovided on master engine A, to a degree in which the respectivepressure regulating valve device 9!] is supplying fluid to chamber I45in the equalizing valve device at substantially the same pressure as isprovided in chamber I44 by the pressure regulating valve device 90 onmaster engine A. Hence the fuel control shaft 8 on slave engine B willnow be occupying substantially the same position as the fuel controlshaft 8 on master engine A, and the power output of the former enginewill therefore be substantially the same as that of the latter engine.

It will now be seen that the pressure of fluid provided in chamber 64 ofmotor 3! on slave engine B equalizes the power output of said enginewith that of master engine A. It should however be noted that the forceproduced by such pressure on the differential areas of diaphragms 42 and43 may not equal that produced by spring 65 incident to the use of shim63, since to obtain the equalization a greater force might be requiredor even a less force would be sumcient, dependent upon the condition ofthe apparatus being controlled, such as slight variations inadjustments, resistances to movement, etc. Thus to obtain equalizationof the output of slave engine B to that of master engine A, the pressureof fluid required in chamber 64 on the slave engine may be eithergreater or less than the chosen degree, such as 25 pounds which wouldprovide equalization if the apparatus on the two engines were identicalin operation. The effect of shim B3 on spring 6| with respect tooperation of motor 30 on the master engine H is the same as would beprovided by this chosen pressure of fluid in chamber 64 in motor 3I onslave engine B. The shim 63 thus constitutes a means on the masterengine for causing automatic operation of the apparatus to equalize theoutput of slave engine B to that of said master engine.

Now let it be assumed that it is desired to increase the amount of fuelsupplied to and thereby the power output of the two engines. Toaccomplish this the operators control device 68 will be operated toincrease the pressure of fluid in pipe 59 to a degree corresponding tothe desired increase in power output. At each of the engines thisincrease in pressure in pipe 59 will be effective through branch pipe 58in control chamber 53" of the respective governor control motor 3Q or 3!and therein act on diaphragm il to move the diaphragm connectingstructure 46 in the direction of the left hand against the opposingforce of regulating spring is. This movement of structure 46 will berelative to the supply valve Bil since said valve is at this time heldagainst movement by the seated release valve '53 and, as a result fluidunder pressure from the supply pipe 5? will flow past said supply valveto the power piston chamber 34.

When the pressure of fluid thus provided in chamber 34 in each of thegovernor control mo tors is then increased to a degree sufficient toovercome the opposing force of spring 4% on the power piston 32, saidpiston will move against and increase the pressure of said springagainst the diaphragm connecting structure 46. Fluid under pressure willcontinue to be supplied past the supply valve 823 to the power pistonchamber 34 until the power piston is moved to a position in which theincreased pressure of spring 40 is sufiicient to counterbalance theincreased pressure of fluid in 5i to move the diaphragm structure 46back into seating engag ment with the supply valve 86 for therebypreventing further flow of fluid under pressure to the power pistonchamber 34. The power piston 32 will then stop in a position, it will benoted, corresponding to the increased pressure of fluid in the controlchamber 5'1, and the corresponding increase in pressure of therespective governor control spring I! should cause a correspondingchange in positionof the-'respectivefuel control shaft 8-and thus a likeincrease in the amount of fuel supplied to the respective engine.

As the fuel control shafts 8 on the two engines are thus operated forincreasing the supply of fuel to theengines, therespective pressureregulating valve devices 99 will be operated to correspondingly increasethe pressure of fluid in dia phragm chambers I44 and 415 of theequalizing valve device I36, and in case the fuel shafts -& on all-ofthe engines assume substantially the same position the pressure of fluidprovided in said'chambers will be substantially the same so that theparts of the equalizing valve device I will remain in the position inwhich they are shown in Fig.5 of the drawings.

However, if when the output of the engines is increased, as justdescribed, the fuel rack 8 on the master engine A should be operated toincrease the supply of fuel to said engine to an amount exceeding thatsupplied to slave engine 5, the pressure regulating valve device 90 onmaster engine A will increase the pressure of fluid in diaphragm chamberM4 to a degree sufficiently in excess of that in chamber I to causeoperation of the equalizing valve device 36 to increase the pressure offluid in diaphragm chamber 5-4 of the governor control motor 3i on slaveengine '13. This increase in pressure of fluid in chamber 64 inmotor 3iwill then causeoperation of said motor to increase the pressure of thegovernor control spring 11 on slave engine B for in turn causingoperation of the fuel control shaft 8 on said engine to increase theamount of fuel supplied to said engine. The fuel control shaft 8 onslave engine B-as itis thus operated to increase the supply of fuel tothe engine, will also operate the respective pressure regulating valvedevice 96 to increase the pressure of fluid in diaphragm chamber M5 inthe equalizing device @3 5 until it substantially equals that in chamberits whereupon spring H4 will move the diaphragms 5'33 and I39 back toneutral position for closing the supply valve I68. When the supply valve!68 is thus closed further flow of fluid to diaphragm chamber as in thegovernor con- 'trol motor '53-! will be prevented, whereupon operationof said motor will cease, as will also movement of the respective fuelcontrol shaft 8, in a position in which the pressure of fluid providedin diaphragm chamber M5 of the equalizing valve device will besubstantially the same as that provided in chamber I43 by operation ofthe pressure regulating device 95 on engine A. Thus with the regulatingvalve device 9!) on slave engine B adjusted to provide substantially thesame pressure of fluid as provided by regulating valve device 90 onmaster engine A, the fuel control shaft 8 on the slave engine will be insubstantially the same position as that on the master engine, so thatthe output of power from the slave engine will be substantially the sameas from the master engine.

On the other hand, let it be assumed that in response to an increase inpressure of fluid in pipe for increasing the power output of the twoengines, the fuel control shaft 8 on slave engine B is operated by thegovernor control motor 3i and the respective governor It to increase thesupply of fuel to said engine to a degree exceeding that obtained onmaster engine A by operation of the governor control motor 30.

Under such a circumstance the pressure regulating valve device 99 onslave engine B will increase the pressure of fluid in diaphragm chamheri 45 in the equalizing valve device 935 to a degree exceeding that whichwill be obtained in chamber I it by operation of the pressure regulatingvalve device $8 on master engine A. As a result, the diaphragms I38 andi3 and the connect ing stem I46 will be moved by the pressure of fluidin diaphragm chamber 5 :25 against the lower pressure of fluid inchamberIt' l and the pressure of spring H5 and thereby act through the valveltd, which will be seated. by spring to draw stem 1&8 in the directionaway from the release valve stem Hit. Spring i552 will however maintainthe head It! on the release valve stem if: in contact with the stem andas result, will pull the release valve iGZ out of contact with its seat.When the release valve is thus opened fluid under pressure wili bevented past said valve from diaphragm chamber 854 in the governorcontrol motor 3| on slave engine 3.

This reduction in pressure in chamber on the differential areas ofdiaphragms ii; and in motor 3! on slave engine B will reduce the forceresulting therefrom and acting in the direction of the left hand, and asa result, the pressure of the regulating spring do on structure #36 willmove said structure in the direction of the right hand against thecontrol pressure of fluid in chamber 5? and the control spring 5!. Withthe supply valve 88 seated against structure 25, this movement of saidstructure will be'relative to the element 5! and the release valve seatmemoer ii, so as to permit spring 'i& to move the release valve "53along with said supply valve and thus out of engagement with its seat.When the release valve is thus opened fluid under pressure will be released from the power piston chamber 3a through passage 3?, chamber 58,chamber it, and thence past said release valve to chamber and from thelatter chamber through passage 55, chamber 38 and passage 39 toatmosphere.

As the pressure of fluid in the power piston chamber 3 3' in governorcontrol motor 3i on slave engine B is thus reduced, the pressure ofregulat ing spring 36 will move the piston 32 in the direction of theleft hand, as viewed in Fig. 3, for thereby actuating cam I9 to reducethe pressure of the respective governor spring ii. The governor Iii onslave engine 13 will then operate to turn the respective fuel controlshaft 8 in a direction to correspondingly reduce the supply of fuel tothe engine, and as a result, the pressure regulating valve device 96 onsaid engine will be operated to correspondingly reduce the pressure offluid in diaphragm chamber M5 of the equalizing valve device I36.

When the fuel control shaft 8 on slave engine Bis thus turned to aposition in which the respective pressure regulating valve device 52reduces the pressure of fluid in diaphragm chamber 555 to substantiallythe same degree as effective in diaphragm chamber IM, the pressure offluid in the latter chamber plus the pressure of spring H5 will deflectthe diaphragms ISQ and I33 and the connecting stem I46 in the directionof chamber I45, and with supply valve I68 held seated by spring M4, thesupply valve H62 will be moved with said diaphragms and finally intocontact with its seat to prevent further release of fluid under pressurefrom chamber lid in the governor control motor 3|.

As soon as the reduction in pressure in chamber 64 in the governorcontrol motor 3! is terminated as just described, the reduction inpressure of regulating spring 4?! on the diaphragm connecting structure46, upon slight further movement the pressure of said spring, willresult in movement of said structure by the remaining fluid pressure inchamber 64 plus that in chamber to the position in which the releasevalve i3 is seated for preventing further release of fluid underpressure from the power piston chamber 354. The power piston 32 willthen stop in a position corresponding substantially to the reducedpressure of fluid in chamber 64 in the governor control motor 3 I, andas a result, the respective speed governor ID will operate to stopmovement of the fuel control shaft 8 on slave engine B in acorresponding position for thereby preventing further reduction in thefuel supply to said engine; thus limiting the degree of such supply tosubstan tially that provided for master engine A.

From the above description it will now be seen that regardless of thepressure of fluid provided in pipe 59 for obtaining different desireddegrees of power output from the engines, the power output of slaveengine B will, if it is different from that on master engine A, beeither increased or decreased automatically as required to obtainsubstantially the same output as on said master engine.

It will be further noted that engine A is automatically renderedeffective as the master engine for regulating or limiting the supply offuel to slave engine B to substantially the same degree as obtained onthe master engine A, by the shim 63 provided in the governor controlmotor 36. The provision of fluid pressure in chamber 64 in the governorcontrol motor 3| on slave engine B, and of means for varying saidpressure in accordance with the relative fuel supply positions of thefuel control shafts 8 on the two engines enables operation of said motorto equalize the power output of slave engine B with that of masterengine A as predetermined by the shim 63 and pressure of controllingfluid in pipe 59.

In the equalizing valve device I36 the springs I14 and I not only insuremovement of the diaphragms I38 and I39 and of the stem I46 to neutralposition in which both the supply valve I58 and the release valve I62are seated, but also prevent said parts overtraveling neutral position,since said springs insure that said neutral position will be obtainedWithout increasing pressure of fluid in chamber I above that in chamberI44, on the one hand, or reducing the pressure of fluid in chamber I45below that in chamber I44, on the other hand. Due to this, movement ofthe fuel shaft 8 on slave engine B in a direction to increase the supplyof fuel to said engine will be positively stopped in a position in whichthe pressure of fluid delivered by the respective pressure regulatingvalve device 9|] may equal but does not exceed that delivered by thepressure regulating valve device 96 on master engine A, so that therewill be no oversupply of fuel to slave engine B with respect to thatsupplied to master engine A. Further, when the fuel shaft 8 on slaveengine B is operated to reduce the supply of fuel to said engine, thesupply will not be reduced to below that on master engine A since theequalizing valve device I36 when it obtains neutral position will stepmovement of the fuel control shaft 8 on slave engine B when the pressureof fluid in diaphragm chamber I45 becomes reduced by operation of therespective pressure regulating value device 90 to substantially, but notbelow, that provided by the regulating valve device 96 on master engineA. ,The springs I14 and I15 in thus preventing operation of theequalizing valve 18 device I36 to cause an oversupply, or anundersupply, as the case may be, of fuel to slave engine B with respectto that being supplied to master engine A renders the whole apparatusstable and positive in operation.

In order to still further stabilize operation of the apparatus, the rateof either increase or decrease in pressure in diaphragm chamber 64 ofthe governor control motor 3| on slave engine B retarded to such adegree, as by the use of choke I16 and the reservoir I11, that thegovernor It on said engine will operate to change the position of therespective fuel control shaft 8 and thereby cause operation of therespective pressure regulating valve device 96 to vary the pressure offluid in diaphragm chamber I45 in the equalizing valve device I36, atleast as rapidly as said motor operates to change adjustment of saidgovernor, so as to ensure that operation of said motor will ceasesubstantially at the instant the equalizing valve device I36 obtains itsneutral position, and for in turning insuring that the fuel controlshaft 8 on slave engine B will positively stop in a positioncorresponding substantially to that of the fuel control shaft 8 onmaster engine A for limiting the amount of fuel supplied to slave engineB to substantially the same degree as being supplied to engine A.

Stability of the apparatus is further insured by springs I'It and I15 inthe equalizing valve device I36 which will maintain the parts of saiddevice in neutral position upon slight changes in pressure of fluid ineither diaphragm chamber I44 or chamber I45 incident to slightvariations in position of the fuel shaft 8 on either engine by operationof the respective speed governor It] to maintain the engine speed orpower output substantially constant against minor variations in load orthe like on the engines.

It is desired to further point out that the sensitivity of theequalizing valve device remains the same through out the full fuelcontrol range of the fuel control shafts 8, i. e., regardless of theopposing pressure of fluid which may be acting in i chambers I44 andI45, since operation of said device depends only upon a chosendifferential between said pressures, and this is very desirable in thatit will ensure prompt equalization of the power output of the slaveengine to that of the master engine when the engines are operated undermaximum load, just as readily as when operating at idling speed andpossibly under no load.

Summary It will now be noted that the improved control apparatusprovides positive automatic equalization of the amount of fuel suppliedto each of any desired number of slave engines with the amount of fuelsupplied to a preselected master engine, so as to substantially equalizethe power output of the several engines, which is particularly desirablewhere several engines are connected to a common load, in order tosubstantially equally divide the load between the engines.

Only one engine can be the master engine and it is conditionedautomatically to so function by the use of shim 63 in the governorcontrol motor 30 on that engine while on the slave engine or enginesthegovernor control motor 3I is automatically adjustable in accordancewith the position of the respective fuel control shaft relative to thaton the master engine, to match the fuel supply to and thereby the poweroutput of the slave engine to that of the master engine.

While only one slave engine B is shown in the 19 drawings, any desirednumber can be controlled from the master engine A through the equalizingpipe 235 as will be obvious.

Having now described my invention what I claim as new and desire tosecure by Letters Patcut is:

l. A control apparatus for equalizing the power output of one primemover with that of another prime mover comprising, an adjustable powercontrol element for each prime mover for varying the power outputthereof, equalizing means having a first position, a second position anda neutral position. intermediate said first and second positions, meansoperable by said equalizing means in. said first position to effectadjustment of said power control element on said one prime mover toincrease the power output of said one prime mover, in said secondposition to effect operation of said power control element on said oneprime mover to reduce the power output of said one prime mover andoperable in said neutral position to maintain said power control elementon said one prime mover against change in adjustment, means adjustablein accordance with the relative power output of said prime mover foreffecting movement of said equalizing means to said first position upona preponderance in output of said other prime mover over that of saidone prime mover, to said second position upon a preponderance in outputof said one prime mover over that of said other prime mover, and to saidneutral position upon equalization of the power output of said one primemover with that of said other prime mover.

2. A. control apparatus for equalizing the power output of one primemover with that of another prime mover comprising, an adjustable powercontrol element for each prime mover for varying the power outputthereof, control means for adjusting said power control elements,equalizing means having a first position, a second position and aneutral position intermediate said first and second positions, meansoperable by said equalizing means in said first position to effectoperation of said control means on said other prime mover to eiiectadjustment of the respective power control element to increase the poweroutput of said other prime mover, and in said second position to effectoperation of said control means on said other prime mover and thereby ofthe respective power control element to reduce the power output of saidother prime mover, and in said neutral position to maintain said controlmeans on said other prime mover against change in adjustment, meansadjustable in accordance with the relative power output of said primemovers for effecting movement of said equalizing means to said firstposition upon a preponderance in output of said one prime mover, and tosaid second position upon a preponderance in output of said other primemover, and means operable to move said equalizing means to said neutralposition upon substantial equalization of the power output of both primemovers.

3. A control apparatus for equalizing the power output of one primemover with that of another prime mover comprising, an adjustable powercontrol element for each prime mover having an idling position andoperable to increase the power output of the respective prime mover inproportion to movement of said element out of said idling position,equalizing means having a first position, a second position and aneutral position intermediate said first and second positions, meansoperable by said equalizing means in said first position to effectoperation of said power control element on said one prime mover toincrease the power output of said one prime mover, and in said secondposition to efiect operation of said power control element on said oneprime mover to reduce the power output of said one prime mover andoperable in said neutral position to maintain said power control elementon said one prime mover against change in adjustment, means adjustablein accordance with the relative positions of said power control elementsfor effecting movement of said equalizing means to said first positionupon a preponderance in output of said one prime mover and to saidsecond position upon a, preponderance in output of said other primemover, and means for efiecting movement of said equalizing means to saidneutral position upon substantial equalize tion of the output of bothprime movers.

4. A control apparatus for equalizing the power output of one primemover with that of another prime mover comprising, first and secondcontrol pipes for said one and other prime movers, an adjustable powercontrol element for each prime mover for varying the power outputthereof, first and second pressure regulating means associatedrespectively with said one and other prime movers and adjustable by therespective prime mover power control element to provide in therespective one of said control pipes fiuid at a pressure proportional tothe power output or the respective prime mover, equalizing means subjectto pressure of fluid provided in said first pipe acting in opposition topressure of fluid provided in said second pipe and movable to a firstposition by the pressure of fluid provided in said first pipe when itexceeds thatprovided in said second pipe, and movable to a secondposition by the pressure of fiuid provided in said second pipe when itexceeds that provided in said first pipe, means for moving saidequalizing means to said neutral position upon substantial equalizationof pressures of fluid in both of said pipes, and means operable in saidfirst position of said equalizing means to effect operation of saidpower control means on said other prime mover to increase the poweroutput thereof, in said second position to effect operation of saidpower control means on said other prime mover to reduce the power outputthereof, and inv said neutral position to maintain said power controlmeans on said other prime mover against change in adjustment.

5.. A control apparatus for equalizing the power output of one primemover with that of another prime mover comprising, first and secondcontrol pipes for said one and other prime movers, an adjustable powercontrol element for each prime mover for varying the power outputthereof, first and second pressure regulating means associatedrespectively with said one and other prim Y overs and adjustable by therespective prime mover power control member to provide in the respective one of said control pipes fiuid at a pressure proportional to thepower output of the respective prime mover, equalizing means subject topressure of fluid provided in said first pipe acting in opposition topressure of fluid provided in said second pipe, and movable to a firstposition by the pressure of fluid provided in said first when it exceedsthat provided in said second pe -e, and movable to a second position bypressure of fluid provided, in-said second pipe when it er:- ceeds thatin said first pipe, spring means acting on said equalizing means,opposing movement thereof to either said first or second positions byfluid under pressure and operable to move same to a neutral positionbetween said first and second positions upon substantial equalization ofthe pressures of fluid in said first and second pipes, and meansoperable in said first position of said equalizing means to effectoperation of said power control means on said other prime mover toincrease the power output thereof, in said second position to effectoperation of said power control means on said other prime mover toreduce the power output thereof, and in said neutral position tomaintain said power control means on said other prime mover againstchange in adjustment.

6. A control apparatus for equalizing the power output of one primemover with that of another prime mover comprising an adjustable powercontrol element for each prime mover, means for adjusting the powercontrol elements on both prime movers to regulate the power outputthereof including fluid motor means on said one prime mover and meansoperable by said motor means to adjust the power control element andthereby the power output of said one prime mover relative to that of theother prime mover, valve means having a first position for supplyingfluid under pressure to said fluid motor means and a second position forreleasing fluid under pressure from said fluid motor means for operatingsame to adjust the respective power control element to either increaseor decrease the power output of said one prime mover relative to that ofsaid other prime mover, said valve means also having a neutral positionintermediate said first and second positions for bottling up the fluidpressure in said motor means, spring means for moving said valve meansto said neutral position, and means adjustable in accordance with thepower output of said prime movers for effecting movement of said valvemeans against said spring means to said first position upon apreponderance in output of said other prime mover over that of said oneprime mover, and to said second position upon a preponderance in outputof said one prime mover over that of said other prime mover, andoperable upon equalization of the output of said one prime mover withthat of said other prime mover to render said spring means effective tomove said valve means to said neutral position.

7. A control apparatus for equalizing the power output of one primemover with that of another prime mover comprising an adjustable powercontrol element for each prime mover, means for adjusting the powercontrol elements on both prime movers to regulate the power outputthereof includin fluid motor means on said one prime mover and meansoperable by said motor means to adjust the power control element andthereby the power output of said one prime mover relative to that of theother prime mover, valve means having a first position for supplyingfluid under pressure to said fluid motor means and a second position forreleasing fluid under pressure from said fluid motor means for operatingsame to adjust the respective power control element to either increaseor decrease the power output of said one prime mover relative to that ofsaid other prime mover, and also having a neutral position intermediatesaid first and second positions for bottling up the fluid pressure insaid motor means, equalizing means subject to opposing pressures offluid in a first chamber and in a second chamber and operable upon apreponderance in pressure in said first chamber over that in said secondchamber to move said valve means to said til first position and upon apreponderance in pressure in said second chamber over that in said firstchamber to move said valve means to said second position, spring meansfor moving said valve means to said neutral position upon substantialequalization of pressures offluid in said first and second chambers, andfirst and second pressure regulating means operable by said powercontrol elements on said one and other prime movers to vary the pressureof fluid in respectively said first and second chambers in proportion tothe power output of the respective prime movers.

8. A control apparatus for equalizing the power output of one primemover with that of another prime mover comprising an adjustable powercontrol element for each prime mover, first and second fluid motors foradjusting respectively the power control elements on said one and otherprime movers, operators control means for varying pressure of fluid insaid motors, power means subject to pressure of fluid in a first chamberand opposing pressure of fluid in a second chamber and movable to afirst position upon a preponderance in pressure in said first chamberover that in said second chamber, and movable to a second position upona preponderance in pressure in said second chamber over that in saidfirst chamber, spring means for moving said power means to a neutralposition inter-mediate said first and second positions upon substantialequalization of the fluid pressures in said first and second chambers, avalve operable by said power means in said first position to supplyfluid under pressure to said first motor, another valve operable by saidpower means in said second position to release fluid under pressure fromsaid first motor, means for closing both of said valves in said neutralposition of said power means, and means operable by said power controlelements on said one and other prime movers to vary the pressure offluid in respectively said first and second chambers in proportion tothe power output of the respective prime movers.

9. A control apparatus for equalizing the power output of two primemovers comprising, a power control element for each prime moveradjustable to vary the power output thereof, first and second fluidmotors for said prime movers for adjusting the respective power controlelements, operators control means connected to both of said motors forsimultaneously controlling operation thereof, said second motorcomprisin fluid pressure controlled bias means for adjusting therespective power control element relative to that on said one primemover in accordance with variations in pressure either above or below achosen pressure of fluid on said bias means, means associated with saidfirst motor for automatically efiect-ing an adjustment of the respectivepower control element corresponding to the adjustment of said powercontrol element on said other prime mover effected by said chosenpressure of fluid acting on said bias means, valve means for increasingand decreasing the pressure of fluid on said bias means and for bottlingup the fluid pressure on said bias means, power means movable to a firstposition upon the preponderance in pressure of fluid in a first chamberover that in a second chamber and movable to a second position upon apreponderance in pressure of fluid in said second chamber over that insaid first chamber and having a neutral position, for controlling saidvalve means, spring means for moving said power means to said neutralposition upon substantial equalization Of the fiuid pressures in said.first and second chambers, and first and second pressure regulatingdevices associated with said one and other prime movers operable by therespective power control elements to vary the pressure of fluid in saidfirst and second chambers in proportion to the adjusted power output ofthe respective prime movers.

10; An apparatus for equalizing the power output of one prime mover withthat of another prime mover comprising, a power control element for eachprime mover adjustable to vary the power output thereof, an equalizingpipe, a regulating device adjustable by said power control element onsaid other prime mover to vary pressure of fluid in equalizing pipe inproportion to the adjusted power output of said other prime mover, asecond pipe, a second pressure regulating device adjustable by saidpower control element on said one prime mover to vary pressure of fluidin said second pipe in proportion to the adjusted power output of saidone prime mover, an equalizing device controlled by pressure of fluid insaid equalizing pipe acting in opposition to pressure of fluid in saidsecond pipe and movable to a first position upon a preponderance inpressure in said equalizing pipe over that in said second pipe, andmovable to a second position upon a. preponderance in pressure of fluidin said second pipe over that in said equalizing pipe, spring means formoving said equalizing device to a neutral position between said firstand second positions upon substantial equalization of pressures in saidequalizing pipe and second pipe, and means operable in said first andsecond positions of said equalizing means to effect adjustment of saidpower control element on said one prime mover to increase and decrease,respectively, the power output of said one prime mover with respect tothat of said other prime mover and operable in said neutral position toprevent change in adjustment of said power control element on said oneprime mover.

JAMES A. CAMPBELL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 943,349 Thoma Dec. 21, 19091,731,389 Melcner Oct. 15, 1929 2,062,824 Rockwell et a1 Dec. 1, 19362,103,274 Sanford Dec. 28, 1937 2,296,979 Byrne Sept. 29, 1942

